JP7068751B2 - Motion detector and mold device - Google Patents

Description

The present invention relates to a motion detection device that detects the motion of an object using magnetism, and a mold device provided with the motion detection device.

A rotation detection device using a magnetic sensor and a magnet utilizing the large Barkhausen effect is known. In this type of rotation detection device, for example, a magnetic sensor is fixed to a support, a magnet is fixed to a rotating body that rotates with respect to the support, and a magnetic sensor detects a change in a magnetic field caused by the rotation of the rotating body. do. The magnetic sensor is formed by winding a coil around a magnetic wire that produces a large Barkhausen effect. The magnetic wire rod that produces the large Barkhausen effect has the property that the magnetization direction is instantly reversed when the external magnetic field changes. The induced current flowing through the coil when the magnetization direction of the magnetic wire is reversed is taken out as a detection signal, and the rotation of the rotating body is detected based on the detection signal. The following Patent Document 1 describes an example of such a rotation detection device.

International Publication No. 2016/002437

According to the rotation detection device described in Patent Document 1, the rotation of an object can be detected. However, there is a demand for a motion detection device suitable for detecting motions other than rotation of an object, such as linear movement or reciprocating motion of an object. For example, a mold device that presses a metal plate has a structure in which the upper mold moves up and down with respect to the lower mold. In order to realize an elevating counter that counts the elevating and lowering of the upper die, a motion detecting device capable of detecting the ascending and descending motion of the upper die is required.

The present invention has been made in view of, for example, the above-mentioned problems, and the subject of the present invention is a motion detection device suitable for detecting motion other than rotation of an object, and a mold device provided with the motion detection device. Is to provide.

In order to solve the above problems, the first motion detection device of the present invention is a motion detection device that detects the relative motion of the first object with respect to the second object, and is provided on the second object. A magnetic sensor having a magnetic element that extends linearly and whose magnetization direction changes according to the direction of a magnetic field applied from the outside , and a magnetic field provided on the second object and applied to the magnetic element are magnetic. In a pair of first magnets forming a first magnetic field that is one direction in the extension direction of the element, and a region provided on the second object and separated from the magnetic element in one direction orthogonal to the extension direction. It has a pair of first yoke pieces arranged apart from each other on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, and the magnetic field lines in the first magnetic field are inside the magnetic element. The direction of the magnetic field provided on the second object and the first setting yoke that sets the path of the magnetic field lines in the first magnetic field so as to pass in one direction in the extension direction of the magnetic element is the direction of the magnetic field. With a pair of second magnets forming a second magnetic field that is in the other direction in the extension direction of the magnetic element and the strength of the magnetic field applied to the magnetic element is stronger than the strength of the first magnetic field applied to the magnetic element. In a region provided on the second object and separated from the magnetic element in another direction orthogonal to the extension direction, the magnetic element is separated from each other on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, respectively. It has a pair of second yoke pieces arranged so that the magnetic field lines in the second magnetic field pass through the magnetic element in the other direction in the extension direction of the magnetic element. When the distance between the second setting yoke to be set and the second setting yoke provided on the first object and moving relative to the second setting yoke and the distance between the second setting yoke and the second setting yoke is a predetermined distance or more. A variable magnetic field that changes the strength of the second magnetic field applied to the magnetic element by changing the path of the magnetic field lines in the second magnetic field when the distance to the second setting yoke is less than the predetermined distance. It is characterized by having a yoke.

In the first motion detection device of the present invention, the magnetic field variable yoke moves relative to the pair of second yoke pieces, and the distance from the pair of second yoke pieces is the predetermined distance. In the above case, the path of the magnetic field lines in the second magnetic field set by the second setting yoke is maintained, and when the distance to the pair of second yoke pieces is less than the predetermined distance, the second The path of the magnetic field lines in the second magnetic field set by the second setting yoke may be changed so that the magnetic field lines in the magnetic field pass through the magnetic field variable yoke.

Further, in the first motion detection device of the present invention, the magnetic field variable yoke is the second setting yoke when the distance between the magnetic field variable yoke and the pair of second yoke pieces is equal to or more than the predetermined distance. By maintaining the path of the magnetic field lines in the second magnetic field set by the above, the strength of the second magnetic field applied to the magnetic element is maintained stronger than the strength of the first magnetic field applied to the magnetic element. Then, when the distance between the magnetic field variable yoke and the pair of second yoke pieces is less than the predetermined distance, the second setting is made so that the magnetic field lines in the second magnetic field pass through the magnetic field variable yoke. By changing the path of the magnetic field lines in the second magnetic field set by the yoke, the strength of the second magnetic field applied to the magnetic element is made weaker than the strength of the first magnetic field applied to the magnetic element. It may be a thing.

Further, in the first motion detection device of the present invention, the shape of each end of the pair of second yoke pieces facing each other is the shape of each end of the pair of first yoke pieces facing each other. It may be different from.

Further, in the first motion detection device of the present invention, the distance between the pair of second yoke pieces may be different from the distance between the pair of first yoke pieces.

Further, in the first motion detection device of the present invention, the distance between the magnetic element and the pair of second yoke pieces is the distance between the magnetic element and the pair of first yoke pieces. It may be different from.

Further, in the first motion detection device of the present invention, the magnetic force of each of the pair of second magnets may be different from the magnetic force of each of the pair of first magnets.

In order to solve the above problems, the second motion detection device of the present invention is a motion detection device that detects the relative motion of the first object with respect to the second object, and is provided on the second object. A magnetic sensor having a magnetic element that extends linearly and whose magnetization direction changes according to the direction of a magnetic field applied from the outside, and a magnetic element provided on the second object and that the direction of the magnetic field applied to the magnetic element is the magnetic element. In a region provided on the second object and separated from the magnetic element in one direction orthogonal to the extension direction, a pair of first magnets forming a first magnetic field which is one direction in the extension direction of the magnetic element. It has a pair of first yoke pieces arranged apart from each other on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, and magnetic lines in the first magnetic field are magnetic in the magnetic element. A first setting yoke that sets the path of magnetic field lines in the first magnetic field so as to pass in one direction in the extension direction of the element, and a magnetic field provided on the second object and applied to the magnetic element are magnetic. In a region provided on the second object and separated from the magnetic element in another direction orthogonal to the extension direction, a pair of second magnets forming a second magnetic field in the extension direction of the element. It has a pair of second yoke pieces arranged apart from each other on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, and the magnetic field lines in the second magnetic field are inside the magnetic element. The first setting yoke moves relative to the second setting yoke that sets the path of the magnetic field lines in the second magnetic field so as to pass in the other direction in the extension direction of the magnetic element, and the first setting yoke. Changing the path of the magnetic field lines in the first magnetic field when the distance to the setting yoke is equal to or greater than the first predetermined distance and when the distance to the first setting yoke is less than the first predetermined distance. The distance between the first variable magnetic field yoke that changes the strength of the first magnetic field applied to the magnetic element and the second set yoke that moves relative to the second set yoke is reduced. The magnetic element is applied by changing the path of the magnetic field lines in the second magnetic field between when the distance is equal to or greater than the second predetermined distance and when the distance from the second setting yoke is less than the second predetermined distance. It is characterized by including a second magnetic field variable yoke that changes the strength of the second magnetic field.

In the second motion detection device of the present invention, the first magnetic field variable yoke is the first magnetic field when the first object moves relative to the second object in one direction. When the distance between the variable yoke and the first setting yoke becomes large and the first object moves relative to the second object in the other direction, the first magnetic field variable yoke and the first magnetic field variable yoke. The first object is provided so that the distance from the setting yoke of 1 is small, and the second magnetic field variable yoke is such that the first object is relative to the second object in one direction. When the distance between the second magnetic field variable yoke and the second setting yoke becomes smaller when moving, the first object moves relative to the second object in the other direction. It may be provided in the first object so that the distance between the second magnetic field variable yoke and the second setting yoke becomes large.

Further, in the second motion detection device of the present invention, the first magnetic field variable yoke is used when the distance between the first magnetic field variable yoke and the first setting yoke is equal to or greater than the first predetermined distance. The path of the magnetic field lines in the first magnetic field set by the first setting yoke is maintained, and the distance between the first magnetic field variable yoke and the first setting yoke is less than the first predetermined distance. Occasionally, the path of the magnetic field lines in the first magnetic field set by the first setting yoke is changed so that the magnetic field lines in the first magnetic field pass through the first magnetic field variable yoke, and the second magnetic field lines are changed. The magnetic field variable yoke is the second magnetic field set by the second setting yoke when the distance between the second magnetic field variable yoke and the second setting yoke is equal to or greater than the second predetermined distance. When the path of the magnetic field lines is maintained and the distance between the second magnetic field variable yoke and the second set yoke is less than the second predetermined distance, the magnetic field lines in the second magnetic field are the second magnetic field variable yoke. The path of the magnetic field lines in the second magnetic field set by the second setting yoke is changed so as to pass through the inside, so that the first object is unidirectionally relative to the second object. By moving, the distance between the first magnetic field variable yoke and the first setting yoke becomes equal to or more than the first predetermined distance, and the distance between the second magnetic field variable yoke and the second setting yoke Is less than the second predetermined distance, the strength of the second magnetic field applied to the magnetic element becomes weaker than the strength of the first magnetic field applied to the magnetic element, and the first object becomes By moving relative to the second object in the other direction, the distance between the first magnetic field variable yoke and the first set yoke becomes less than the first predetermined distance, and the second When the distance between the magnetic field variable yoke and the second setting yoke is equal to or greater than the second predetermined distance, the strength of the second magnetic field applied to the magnetic element is applied to the magnetic element. It may be stronger than the strength of the magnetic field.

Further, in the first or second motion detection device of the present invention, one magnet of the pair of first magnets and one magnet of the pair of second magnets are a single magnet. It is formed by one common magnet, and the other magnet of the pair of first magnets and the other magnet of the pair of second magnets are formed by a single second common magnet. It may be that.

Further, in the first or second motion detection device of the present invention, the number of times the magnetization direction of the magnetic element changes from one direction in the extension direction of the magnetic element to the other in the extension direction and the magnetization direction of the magnetic element are determined. It is preferable to include a counting circuit that counts one or both of the number of times the magnetic element changes from the other direction in the extension direction to one direction in the extension direction.

Further, in the first or second motion detection device of the present invention, the magnetic element is preferably a magnetic element that produces a large Barkhausen effect.

In order to solve the above problems, the mold apparatus of the present invention has a first mold piece and a second mold piece, and the first mold piece and the second mold piece are combined with each other. A mold that sandwiches a work material and presses the work material, a first support portion that supports the first mold piece, and a second mold piece are supported. The first support portion is moved relative to the second support portion so that the second support portion and the first mold piece come into contact with and separate from the second mold piece. A third support portion that can be supported and the first or second motion detection device of the present invention are provided, the first object is the first support portion, and the second object is the second object. A second support, the motion detection device detects the relative movement of the first support with respect to the second support.

According to the present invention, it is possible to realize a motion detection device suitable for detecting motion other than rotation of an object, and it is also possible to provide a mold device provided with the operation detection device.

It is explanatory drawing which shows the mold apparatus provided with the elevating counter which is the 1st Embodiment of the motion detection apparatus of this invention. It is a perspective view which shows the appearance of the elevating counter of the 1st Embodiment of this invention. It is explanatory drawing which shows typically the state which the elevating counter of the 1st Embodiment of this invention is seen from the front. It is explanatory drawing which shows the cross section of the elevating counter seen from the direction of arrow IV-IV in FIG. It is explanatory drawing which shows the elevating counter seen from the arrow VV direction in FIG. It is explanatory drawing which shows the magnetic sensor, the count circuit and the connector in the elevating counter of the 1st Embodiment of this invention. It is explanatory drawing which shows the operation of the elevating counter of the 1st Embodiment of this invention. It is explanatory drawing which shows the elevating counter of the 2nd Embodiment of this invention. It is explanatory drawing which shows the elevating counter of the 3rd Embodiment of this invention. It is explanatory drawing which shows the example which changed the mounting direction of the elevating counter of 1st Embodiment of this invention to a mold apparatus. It is explanatory drawing which shows the elevating counter seen from the arrow XI-XI direction in FIG.

Hereinafter, some embodiments of the motion detection device of the present invention will be described with reference to the drawings. In the following description, when referring to the directions of upper (U), lower (D), left (L), right (R), front (F) or rear (B), the left portion of FIGS. 1 to 9 Follow the arrow drawn in.

[First Embodiment]
FIG. 1 shows a mold device 1 provided with an elevating counter 21 which is the first embodiment of the motion detection device of the present invention. In FIG. 1, the mold device 1 is a device that presses a work material 2 which is a metal plate. The mold device 1 includes a mold 3 having a lower mold 4 and an upper mold 5. According to the die 3, the work material 2 is sandwiched between the lower mold 4 and the upper mold 5, and the work material 2 can be pressed. The lower mold 4 and the upper mold 5 are arranged so as to face each other vertically, the lower mold 4 is supported by the lower mold holder 6, and the upper mold 5 is supported by the upper mold holder 7. Further, the upper mold holder 7 is supported by the lower mold holder 6 so as to be able to move up and down via four guide posts (only two are shown) provided at the four corners thereof. By these guide posts 8, the upper mold holder 7 is movably supported with respect to the lower mold holder 6 so that the upper mold 5 comes into contact with (approaches, separates from) the lower mold 4. Further, each guide post 8 is provided with a spring 9 for urging the upper mold holder 7 upward. Further, the mold device 1 is provided with an actuator (not shown) for lowering the upper mold holder 7. When the actuator is turned on, the upper die holder 7 is lowered, and when the actuator is turned off, the upper die holder 7 is raised by the urging force of each spring 9. When the upper die holder 7 is lowered, the lower die 4 and the upper die 5 are combined, and the work material 2 is pressed. The upper mold 5 is a specific example of the "first mold piece" in the description of the claims, and the lower mold 4 is a specific example of the "second mold piece" in the description of the claims. Yes, the upper mold holder 7 is a specific example of the "first support portion" in the description of the claims, and the lower mold holder 6 is a specific example of the "second support portion" in the description of the claims. Yes, the guide post 8 is a specific example of the "third support portion" in the description of the claims.

Further, the mold device 1 is provided with an elevating counter 21. The elevating counter 21 is a device that detects the elevating motion of the upper die 5 and counts the elevating and lowering of the upper die 5 based on the detection result. The elevating counter 21 is attached between the lower mold holder 6 and the upper mold holder 7 via the counter holders 10 and 11.

FIG. 2 shows the appearance of the elevating counter 21. FIG. 3 schematically shows a state in which the elevating counter 21 is viewed from the front. FIG. 4 shows a state in which the elevating counter 21 is viewed from the direction of arrow IV-IV in FIG. FIG. 5 shows a state in which the elevating counter 21 is viewed from the arrow VV direction in FIG. FIG. 6 shows the magnetic sensor 22, the count circuit 45, and the connector 49. In FIGS. 3 to 5, the substrate 44, the count circuit 45, and the connector 49 are not shown.

As shown in FIG. 2, the elevating counter 21 includes a magnetic sensor 22, a left magnet 31, a right magnet 32, a lower setting yoke 33, an upper setting yoke 36, a magnetic field variable yoke 41, a substrate 44, a counting circuit 45, and a connector 49. It is equipped with. Among these components constituting the elevating counter 21, those excluding the magnetic field variable yoke 41 are fixed to the lower mold holder 6 via the counter holder 10 as shown in FIG. On the other hand, the magnetic field variable yoke 41 is fixed to the upper mold holder 7 via the counter holder 11. The upper mold holder 7 is a specific example of the "first object" in the description of the claims, and the lower mold holder 6 is a specific example of the "second object" in the description of the claims.

As shown in FIG. 6, the magnetic sensor 22 has a magnetic element 23, a coil 24, a bobbin 25, and a pair of terminals 26.

The magnetic element 23 is an element that extends linearly and whose magnetization direction changes according to the direction of a magnetic field applied from the outside. The magnetic element 23 in this embodiment is a magnetic element that produces a large Barkhausen effect. The magnetic element 23 is a wire rod formed of, for example, a semi-hard magnetic material containing iron and cobalt, having a diameter of, for example, about 0.1 mm to 1 mm, and a length of, for example, about 10 mm to 30 mm. The magnetic element 23 is formed, for example, by drawing the semi-hard magnetic material and twisting it a plurality of times while changing the direction. The magnetic element 23 has uniaxial anisotropy in which the direction in which magnetization is easy is the axial direction of the magnetic element 23. Further, in the magnetic element 23, the coercive force is larger in the central side portion than in the outer peripheral side portion. The magnetic element 23 has a property that the magnetization direction of the magnetic element 23 (the outer peripheral side portion thereof) suddenly reverses in response to a change in the direction of the external magnetic field.

The magnetic element 23 is housed inside, for example, a resin bobbin 25. The coil 24 is formed by winding a winding around the outer peripheral side of the bobbin 25. As a result, a structure is formed in which the magnetic element 23 penetrates the center of the coil 24. Further, the pair of terminals 26 are provided on both ends of the bobbin 25, respectively. Each terminal 26 is formed of a conductive material, and the end of the winding is connected to one end of each terminal 26. As shown in FIG. 3, the magnetic sensor 22 is arranged so that the extension direction of the magnetic element 23 is the left-right direction in the elevating counter 21.

The left magnet 31 is provided on the left side of the magnetic sensor 22. The right magnet 32 is provided on the right side of the magnetic sensor 22. The left magnet 31 and the right magnet 32 are permanent magnets, for example, ferrite magnets. The shapes of the left side magnet 31 and the right side magnet 32 in the present embodiment are each rectangular parallelepiped, but these shapes are not particularly limited, and may be, for example, a columnar shape or a polygonal columnar shape. Further, the left side magnet 31 is magnetized so that the upper side thereof is the S pole and the lower side is the N pole. The right side magnet 32 is magnetized in the direction opposite to the magnetizing direction of the left side magnet 31. That is, the right side magnet 32 is magnetized so that the upper side thereof is the north pole and the lower side is the south pole. The left magnet 31 is a specific example of the "first common magnet" in the claims, and the right magnet 32 is a specific example of the "second common magnet" in the claims.

As shown in FIG. 3, the lower setting yoke 33 is provided below the magnetic sensor 22, the left magnet 31, and the right magnet 32. The lower setting yoke 33 has a pair of yoke pieces 34, 35. Each yoke piece 34, 35 is formed in a flat plate shape by a soft magnetic material such as iron. One yoke piece 34 extends in the left-right direction from the lower part of the left magnet 31 to the lower part of the left part of the magnetic sensor 22, and the right end 34A of the yoke piece 34 is in the center of the magnetic sensor 22 in the left-right direction. Has not reached. The other yoke piece 35 is arranged symmetrically with the yoke piece 34. That is, the yoke piece 35 extends in the left-right direction from the lower part of the right magnet 32 to the lower part of the right part of the magnetic sensor 22, but the left end 35A of the yoke piece 35 is in the center of the magnetic sensor 22 in the left-right direction. Not reached.

Further, as shown in FIG. 3, the pair of yoke pieces 34, 35 and the magnetic sensor 22 are separated from each other. The distance D1 between the pair of yoke pieces 34, 35 and the axis of the magnetic element 23 is set to a predetermined value. The yoke piece 34 is in contact with the lower end surface of the left magnet 31, and the yoke piece 35 is in contact with the lower end surface of the right magnet 32.

Further, as shown in FIG. 4, each yoke piece 34, 35 has a rectangular or square shape when viewed upward. The dimensions of the yoke pieces 34 and 35 in the front-rear direction are larger than the dimensions of the magnetic sensor 22 in the front-rear direction. In the upward view, the magnetic sensor 22 is arranged at the center of each of the yoke pieces 34 and 35 in the front-rear direction. Further, the distance D3 between the right end 34A of the yoke piece 34 and the left end 35A of the yoke piece 35 is set to a predetermined value. The lower setting yoke 33 is a specific example of the "first setting yoke" in the description of the claims, and the yoke pieces 34 and 35 are specific examples of the "first yoke piece" in the description of the claims. This is an example.

As shown in FIG. 3, the upper setting yoke 36 is provided above the magnetic sensor 22, the left magnet 31, and the right magnet 32. The upper setting yoke 36 has a pair of yoke pieces 37 and 38. Each yoke piece 37, 38 is formed in a flat plate shape by a soft magnetic material such as iron. One yoke piece 37 extends in the left-right direction from above the left magnet 31 to above the left portion of the magnetic sensor 22, and the right end 37A of the yoke piece 37 is centered in the left-right direction of the magnetic sensor 22. Has not reached. The other yoke piece 38 is arranged symmetrically with the yoke piece 37. That is, the yoke piece 38 extends in the left-right direction from above the right magnet 32 to above the right portion of the magnetic sensor 22, but the left end 38A of the yoke piece 38 is centered in the left-right direction of the magnetic sensor 22. Has not reached.

Further, as shown in FIG. 3, the pair of yoke pieces 37, 38 and the magnetic sensor 22 are separated from each other. The distance D2 between the pair of yoke pieces 37, 38 and the axis of the magnetic element 23 is set to a value smaller than the distance D1 between the pair of yoke pieces 34, 35 and the axis of the magnetic element 23. The yoke piece 37 is in contact with the upper end surface of the left magnet 31, and the yoke piece 38 is in contact with the upper end surface of the right magnet 32.

Further, as shown in FIG. 5, each yoke piece 37, 38 has a substantially rectangular or square shape when viewed upward. However, since the right front corner portion and the right rear corner portion of the yoke piece 37 are cut out, a protrusion 39 projecting to the right is formed at the center portion in the front-rear direction of the right end side portion of the yoke piece 37. .. Similarly, a protruding portion 40 projecting to the left is formed at the central portion in the front-rear direction of the left end side portion of the yoke piece 38. The protrusions 39 and 40 are located above (directly above) the magnetic sensor 22. Further, the distance D4 between the right end 37A of the yoke piece 37 (the tip of the protruding portion 39) and the left end 38A of the yoke piece 38 (the tip of the protruding portion 40) is the right end 34A of the yoke piece 34 and the left end of the yoke piece 35. It is set to a value substantially equal to the distance D3 between 35A. Further, the dimensions from the frontmost end to the rearmost end of each of the yoke pieces 37 and 38 (that is, the portion of the yoke piece 37 that is not the protruding portion 39 and the portion of the yoke piece 38 that is not the protruding portion 40 in the front-rear direction. The dimension) is set to a value larger than the dimension in the front-rear direction of the magnetic sensor 22. The upper setting yoke 36 is a specific example of the "second setting yoke" in the description of the claims, and the yoke pieces 37 and 38 are specific examples of the "second yoke piece" in the description of the claims. Is.

As shown in FIG. 2, the magnetic field variable yoke 41 is formed of a soft magnetic material such as iron into a rectangular or square plate shape in an upward view. Further, the magnetic field variable yoke 41 is arranged above the upper setting yoke 36. Further, the magnetic field variable yoke 41 is arranged so as to face the upper setting yoke 36, and the lower surface of the magnetic field variable yoke 41 is parallel to the upper surfaces of the yoke pieces 37 and 38 of the upper setting yoke 36. Further, no other member is interposed between the magnetic field variable yoke 41 and the upper setting yoke 36. Further, in upward view, a part of the magnetic field variable yoke 41 is arranged so as to overlap the yoke piece 37 of the upper setting yoke 36, and the other part of the magnetic field variable yoke 41 is arranged so as to overlap the yoke piece 38 of the upper setting yoke 36. Has been done. In the present embodiment, in upward view, the left portion of the magnetic field variable yoke 41 overlaps the right portion of the yoke piece 37, and the right portion of the magnetic field variable yoke 41 overlaps the yoke piece 38 and the left portion. Further, the central portion in the left-right direction of the magnetic field variable yoke 41 is located above the central portion in the left-right direction of the magnetic sensor 22.

Further, as shown in FIG. 1, the magnetic field variable yoke 41 is fixed to the upper die holder 7 via the counter holder 11 and moves up and down together with the upper die holder 7 and the upper die 5. On the other hand, the magnetic sensor 22, the left magnet 31, the right magnet 32, the lower setting yoke 33, the upper setting yoke 36, the substrate 44, the count circuit 45, and the connector 49 are fixed to the lower mold holder 6 via the counter holder 10. , Is immovable in the mold device 1. Therefore, as shown by the arrow M in FIG. 3, the magnetic field variable yoke 41 moves in the vertical direction above the upper setting yoke 36 as the upper mold holder 7 moves up and down. That is, when the upper mold holder 7 is lowered, the distance between the magnetic field variable yoke 41 and the upper setting yoke 36 in the vertical direction becomes smaller. On the other hand, when the upper mold holder 7 rises, the distance between the magnetic field variable yoke 41 and the upper setting yoke 36 increases in the vertical direction.

Further, in FIG. 2, the count circuit 45 has a function of counting the number of times the upper mold holder 7 is lowered and raised based on the detection signal output from the magnetic sensor 22, and the number of times the upper mold holder 7 is lowered and raised (the number of times the upper mold holder 7 is lowered and raised ( Hereinafter, this is referred to as a “elevation count value”), and has a function of storing the ascending / descending count value to the outside and a function of supplying electric power to each part in the count circuit 45. As shown in FIG. 6, the counting circuit 45 has a control unit 46, a storage unit 47, and a power generation unit 48. The control unit 46 counts the number of times the upper mold holder 7 is lowered and raised based on the detection signal output from the magnetic sensor 22, and updates the ascending / descending count value stored in the storage unit 47, and the storage unit 47. Performs processing such as outputting the ascending / descending count value stored in to the outside. Further, the storage unit 47 stores the ascending / descending count value. Further, the power generation unit 48 generates electric power using the detection signal output from the magnetic sensor 22, and supplies the electric power to the control unit 46 and the storage unit 47. The control unit 46 is formed of, for example, a semiconductor integrated circuit, the storage unit 47 is formed of a semiconductor storage element, and the power generation unit 48 is formed of an electric circuit.

The connector 49 is connected to the count circuit 45. For example, the connector 49 and an external device can be connected with a cable, and the update count value stored in the storage unit 47 can be output to the external device via the connector 49.

The count circuit 45, the connector 49, and the magnetic sensor 22 are fixed to the substrate 44 as shown in FIG. Further, a pair of yoke pieces 34 and 35 of the count circuit 45, a substrate 44 to which the connector 49 and the magnetic sensor 22 are fixed, a left magnet 31, a right magnet 32, a lower setting yoke 33, and a pair of yokes of the upper setting yoke 36. The pieces 37 and 38 are fixed via fixing members (not shown) so that these components are arranged in the arrangement shown in FIG.

FIG. 7 shows the operation of the elevating counter 21. As described above, in the mold device 1, when the actuator is turned on, the upper mold holder 7 is lowered, and when the actuator is turned off, the upper mold holder 7 is raised by the urging force of each spring 9. Here, the position where the actuator is turned on and the upper die holder 7 is fully lowered is called the "lower limit position", and the position where the actuator is turned off and the upper die holder 7 is fully raised by the urging force of each spring 9 is called the "upper limit position". "Position". For example, when the upper mold holder 7 is in the upper limit position, the magnetic field variable yoke 41 is located at a position separated from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more, as shown in FIG. 7 (A). It is in. On the other hand, when the upper mold holder 7 descends and moves to its lower limit position, the magnetic field variable yoke 41 moves upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36, as shown in FIG. 7B. Move to a position less than the above predetermined distance. H in FIGS. 7 (A) and 7 (B) both indicate a position separated by a predetermined distance from the upper surface of each of the yoke pieces 37 and 38 of the upper setting yoke 36. In FIG. 7A, the position of the magnetic field variable yoke 41 is higher than the position H, and in FIG. 7B, the position of the magnetic field variable yoke 41 is lower than the position H.

Further, in FIG. 7, the N pole at the lower part of the left magnet 31, the S pole at the lower part of the right magnet 32, and the lower setting yoke 33 have the direction of the magnetic field in one direction (right direction) in the extension direction of the magnetic element 23. A first magnetic circuit is formed in which a first magnetic field is applied to the magnetic element 23. Further, the north pole of the upper part of the right side magnet 32, the S pole of the upper part of the left side magnet 31, and the upper setting yoke 36 have a second magnetic field whose magnetic field direction is the other direction (left direction) in the extension direction of the magnetic element 23. Is applied to the magnetic element 23 to form a second magnetic circuit.

Further, as shown in (1) FIG. 3, the distance D2 between the yoke pieces 37 and 38 of the upper setting yoke 36 and the axis of the magnetic element 23 is set between the yoke pieces 34 and 35 of the lower setting yoke 33 and the magnetic element. It is smaller than the distance D1 between the 23 axes. Further, as shown in (2) FIG. 5, protrusions 39 and 40 are formed on the right end side portion of the yoke piece 37 of the upper setting yoke 36 and the left end side portion of the yoke piece 38. (3) As shown in FIGS. 4 and 5, between the right end 37A (tip of the protrusion 39) of the yoke piece 37 and the left end 38A (tip of the protrusion 40) of the yoke piece 38 in the upper setting yoke 36. The distance D4 of is equal to the distance D3 between the right end 34A of the yoke piece 34 and the left end 35A of the yoke piece 35 in the lower setting yoke 33. Due to these configurations (1) to (3), the magnetic field variable yoke 41 is located at a position separated from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more, as shown in FIG. 7 (A). The strength of the second magnetic field applied to the magnetic element 23 is stronger than the strength of the first magnetic field applied to the magnetic element 23.

As shown in FIG. 7 (A), when the magnetic field variable yoke 41 is located at a position more than a predetermined distance upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36, the magnetic field is stronger than the first magnetic field. The magnetic field of 2 is applied to the magnetic element 23. The path of the magnetic field line in the second magnetic field travels to the left in the yoke piece 38 of the upper setting yoke 36 from the north pole of the upper part of the right magnet 32, and from the protruding portion 40 of the yoke piece 38 to the right end side portion of the magnetic element 23. Enter, proceed to the left in the magnetic element 23, enter into the protruding portion 39 of the yoke piece 37 of the upper setting yoke from the left end side portion of the magnetic element 23, proceed to the left in the yoke piece 37, and proceed to the left in the left magnet 31. It is a route to the upper S pole. As a result, the magnetization direction of the magnetic element 23 becomes a direction corresponding to the direction of the second magnetic field, that is, the left direction.

On the other hand, as shown in FIG. 7B, when the magnetic field variable yoke 41 descends and moves upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 to a position less than the predetermined distance, the second The path of the magnetic field lines in the magnetic field is changed by the magnetic field variable yoke 41. Specifically, the magnetic field variable yoke 41 descends and moves upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 to a position less than the predetermined distance, whereby the magnetic field variable yoke 41 becomes the yoke piece 37. , 38 approach each. When the magnetic field variable yoke 41 approaches each of the yoke pieces 37 and 38, the magnetic field line in the second magnetic field enters the right side portion of the magnetic field variable yoke 41 from the yoke piece 38 and travels to the left in the magnetic field variable yoke 41 to the magnetic field. It comes into the yoke piece 37 from the left side portion of the variable yoke 41. As a result, the magnetic field lines that enter the right end side portion of the magnetic element 23 from the protruding portion 40 of the yoke piece 38, proceed to the left in the magnetic element 23, and enter the protruding portion 39 of the yoke piece 37 from the left end side portion of the magnetic element 23. It becomes coarse and the strength of the second magnetic field applied to the magnetic element 23 becomes weaker than the strength of the first magnetic field applied to the magnetic element 23.

As shown in FIG. 7B, the path of the magnetic field line in the first magnetic field travels to the right in the yoke piece 34 of the lower setting yoke 33 from the north pole of the lower part of the left magnet 31, and of the yoke piece 34. Enter the left end side portion of the magnetic element 23 from the right end side portion, proceed to the right in the magnetic element 23, enter the left end side portion of the yoke piece 35 of the lower setting yoke 33 from the right end side portion of the magnetic element 23, and enter the yoke piece. Proceeding to the right in 35, it becomes a path to the S pole above the right magnet 32. Therefore, when the strength of the second magnetic field applied to the magnetic element 23 becomes weaker than the strength of the first magnetic field applied to the magnetic element 23, the magnetization direction of the magnetic element 23 coincides with the direction of the first magnetic field. That is, to the right.

As can be seen from the above description, the magnetic field variable yoke 41 is located on the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 from a position separated upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more. When the upper mold holder 7 is moved upward from the upper limit position to a position less than the predetermined distance, that is, when the upper die holder 7 is moved from the upper limit position to the lower limit position, the magnetization direction of the magnetic element 23 is reversed from the left direction to the right direction. As a result, for example, a sharp pulse current in the positive direction flows through the coil 24 due to electromagnetic induction, and this pulse current is output from the magnetic sensor 22 to the count circuit 45 as a detection signal. On the other hand, the magnetic field variable yoke 41 moves upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 to a predetermined distance upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36. When the upper mold holder 7 is moved from the lower limit position to the upper limit position, that is, the magnetization direction of the magnetic element 23 is reversed from the right direction to the left direction. As a result, for example, a sharp pulse current in the negative direction flows through the coil 24 due to electromagnetic induction, and this pulse current is output from the magnetic sensor 22 to the count circuit 45 as a detection signal. The control unit 46 of the counting circuit 45 counts the positive and negative pulses in the detection signal thus output from the magnetic sensor 22. As a result, the number of times the upper mold holder 7 is lowered and raised can be counted.

As described above, in the elevating counter 21 of the first embodiment of the present invention, the magnetic field is generated by the first magnetic circuit having the N pole of the left magnet 31, the S pole of the right magnet 32, and the lower setting yoke 33. A first magnetic field whose direction is one direction (right direction) in the extension direction of the magnetic element 23 is applied to the magnetic element 23, and a second magnetic field having an N pole of the right side magnet 32, an S pole of the left side magnet 31, and an upper setting yoke 36. By the circuit, a second magnetic field is applied to the magnetic element 23 in which the direction of the magnetic field is the other direction (left direction) in the extension direction of the magnetic element 23 and the strength of the magnetic field is stronger than the strength of the first magnetic field. Then, when the magnetic field variable yoke 41 that moves up and down together with the upper mold holder 7 is located at a position separated from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more, the first set by the upper setting yoke 36. When the path of the magnetic field lines in the magnetic field of 2 is maintained and the magnetic field variable yoke 41 is located upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 at a position less than the predetermined distance, the magnetic field lines in the second magnetic field are generated. By passing through the magnetic field variable yoke 41, the path of the magnetic field line in the second magnetic field set by the upper setting yoke 36 is changed, and the strength of the second magnetic field applied to the magnetic element 23 is changed to the magnetic element. It is weaker than the strength of the first magnetic field applied to 23. By setting and changing the magnetic field in this way, when the upper mold holder 7 descends, the magnetization direction of the magnetic element 23 is reversed from the other direction to one direction, and when the upper mold holder 7 rises, the magnetic element 23 Is inverted from one direction to the other, and the descent and ascent of the upper mold holder 7 are counted based on the detection signal generated by the inversion of the magnetization direction of the magnetic element 23. According to the elevating counter 21 having such a configuration, it is possible to detect the elevating of the upper mold holder 7 based on a small amount of movement of the magnetic field variable yoke 41, so that a small elevating counter 21 can be realized.

Further, according to the elevating counter 21 of the present embodiment, the elevating counter 21 can detect the elevating and lowering of the upper die holder 7 only by attaching the magnetic field variable yoke 41 which is one iron plate to the upper die holder 7. Can increase the durability of. That is, when a large number of parts such as magnets are attached to the upper die holder 7, the parts attached to the upper die holder 7 fall off due to vibration when the upper die holder 7 is raised and lowered, and the raising and lowering counter 21 fails. The possibility increases. According to this embodiment, the possibility of such a failure of the elevating counter 21 can be reduced. For example, if the magnetic field variable yoke 41 is fixed to the counter holder 11 by bolting or the like, the magnetic field variable yoke 41 hardly falls off from the counter holder 11. If the only component attached to the counter holder 11 is the magnetic field variable yoke 41, the component will hardly fall off from the counter holder 11.

Further, according to the elevating counter 21 of the present embodiment, the path of the magnetic field line in the first magnetic field is set by using the lower setting yoke 33, and the path of the magnetic field line in the second magnetic field is set by using the upper setting yoke 36. are doing. In this way, by controlling the path of the magnetic field lines by using the lower setting yoke 33 and the upper setting yoke 36, it is possible to suppress the leakage of magnetism from the elevating counter 21 to the outside, and it is possible to improve the magnetic efficiency. can. Therefore, the left side magnet 31 and the right side magnet 32 can be made smaller, and the elevating counter 21 can be made smaller. Further, by controlling the path of the magnetic field lines by using the lower setting yoke 33 and the upper setting yoke 36, the first magnetic field or the above-mentioned first magnetic field is affected by the magnetic noise (external magnetic noise) from the outside of the elevating counter 21. It is possible to suppress the disturbance of the second magnetic field. Therefore, it is possible to improve the detection accuracy and the stability of the raising and lowering of the upper mold holder 7.

Further, in the elevating counter 21 of the present embodiment, the lower setting yoke 33 is left and right (magnetic element) in a region below the magnetic element 23 (a region separated from the magnetic element 23 in one direction orthogonal to its extension direction). It has a pair of yoke pieces 34, 35 arranged apart from each other on one side and the other side in the extension direction of 23. With this configuration, the path of the magnetic field lines can be easily set so that the magnetic field lines in the first magnetic field pass through the magnetic element 23 in one direction in the extension direction. Further, the upper setting yoke 36 is left and right (one side and the other side in the extension direction of the magnetic element 23) in the region above the magnetic element 23 (a region separated from the magnetic element 23 in another direction orthogonal to the extension direction). It has a pair of yoke pieces 37, 38 arranged apart from each other. With this configuration, the path of the magnetic field lines can be easily set so that the magnetic field lines in the second magnetic field pass through the magnetic element 23 in the other direction in the extension direction.

Further, in the elevating counter 21 of the present embodiment, the protrusions 39 and 40 are formed on the right end side portion of the yoke piece 37 of the upper setting yoke 36 and the left end side portion of the yoke piece 38, respectively, whereas the lower portion is formed. No protrusion is formed on the right end side portion of the yoke piece 34 of the side setting yoke 33 and the left end side portion of the yoke piece 35. In this way, the shape of the pair of yoke pieces 37, 38 facing each other in the upper setting yoke 36 is the shape of the end portions of the pair of yoke pieces 34, 35 facing each other in the lower setting yoke 33. By making them different, it is possible to create a difference in strength between the first magnetic field and the second magnetic field.

Further, in the elevating counter 21 of the present embodiment, the distance D2 between the yoke pieces 37 and 38 of the upper setting yoke 36 and the axis of the magnetic element 23 is set between the yoke pieces 34 and 35 of the lower setting yoke 33 and the magnetic element. The value is set to be smaller than the distance D1 between the 23 axes. In this way, the distance D2 between the yoke pieces 37, 38 of the upper setting yoke 36 and the axis of the magnetic element 23 is the distance between the yoke pieces 34, 35 of the lower setting yoke 33 and the axis of the magnetic element 23. By making it different from D1, it is possible to create a difference in strength between the first magnetic field and the second magnetic field.

Further, in the elevating counter 21 of the present embodiment, the magnetic sensor 22 has a magnetic element 23 that produces a large Barkhausen effect. According to the magnetic element 23 that produces the large Barkhausen effect, a pulse current that changes instantaneously due to a change in the direction of the external magnetic field can be obtained, and the ascending / descending motion of the upper mold holder 7 is detected based on this pulse current. can do. Therefore, no power supply is required to detect the ascending / descending motion of the upper die holder 7. Therefore, a power supply circuit for supplying power from the outside or a battery is not required, the elevating counter 21 can be miniaturized, and maintenance work such as battery replacement can be eliminated.

Further, the elevating counter 21 of the present embodiment includes a counting circuit 45 for counting the descent and ascent of the upper mold holder 7. Therefore, according to the elevating counter 21, a compact non-power supply counter can be realized.

Further, in the elevating counter 21 of the present embodiment, whether or not the distance between the magnetic field variable yoke 41 and the upper setting yoke 36 has changed from a predetermined distance or more to less than a predetermined distance, or the distance between them is less than a predetermined distance. The motion of the moving object is detected based on whether or not the change is made by a predetermined distance or more. As a result, according to the elevating counter 21 of the present embodiment, for example, the magnetic field variable yoke 41 is attached to a movable object, and the portion of the elevating counter 21 excluding the magnetic field variable yoke 41 is installed at a position less than a predetermined distance from a specific observation point. By doing so, it is possible to detect that the movable object has passed the specific observation point. In this case, it is not limited in what kind of trajectory the movable object moves through the specific observation point. That is, even if the movable object passes through the specific observation point in the middle of the linear reciprocating motion, or the movable object passes through the specific observation point in the middle of the circular reciprocating motion, the movable object A moving object passes through the specific observation point even if the moving object passes through the specific observation point while moving in a circular motion or when the moving object passes through the specific observation point while moving in a complicated trajectory. This can be detected by the elevating counter 21. As described above, according to the elevating counter 21 of the present embodiment, it is possible to detect various forms of motion of a movable object.

Further, according to the mold device 1 provided with the elevating counter 21 of the present embodiment, the upper mold 5 (upper mold holder 7) can be used without supplying power from the outside and without using a battery. You can count ups and downs. As described above, according to the present embodiment, while having the elevating count function of the upper die 5, maintenance such as battery replacement is not required, and wiring of the power cable is not required at the time of use, so that the metal is easy to handle. A mold device can be realized.

[Second Embodiment]
FIG. 8 shows an elevating counter 61 according to a second embodiment of the present invention. In FIG. 8, the same components as those of the elevating counter 21 of the first embodiment of the present invention are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 3, the elevating counter 21 of the first embodiment described above has a left side magnet 31 and a right side magnet 32, and the left side magnet 31 and the right side magnet 32 form a pair of the first magnetic circuit. It is used as a magnet of the above and is used as a pair of magnets forming a second magnetic circuit. On the other hand, the elevating counter 61 of the present embodiment separately has a pair of magnets forming the first magnetic circuit and a pair of magnets forming the second magnetic circuit.

That is, as shown in FIG. 8, the left magnet 62 forming the first magnetic circuit is provided on the lower left side of the magnetic sensor 22, and the right magnet 63 forming the first magnetic circuit is a magnetic sensor. It is provided on the lower right side of 22. Further, the left side magnet 62 is arranged so that the upper side thereof is the S pole, and the right side magnet 63 is arranged so that the upper side thereof is the N pole. Further, the upper end surface of the left magnet 62 contacts the lower surface of the left end side portion of the left yoke piece 34 of the lower setting yoke 33, and the upper end surface of the right magnet 63 is the right end of the right yoke piece 35 of the lower setting yoke 33. It is in contact with the lower surface of the side part.

Further, the left magnet 64 forming the second magnetic circuit is provided on the upper left side of the magnetic sensor 22, and the right magnet 65 forming the second magnetic circuit is provided on the upper right side of the magnetic sensor 22. Has been done. Further, the left side magnet 64 is arranged so that the lower side thereof is the north pole, and the right side magnet 65 is arranged so that the lower side thereof is the south pole. Further, the lower end surface of the left magnet 64 contacts the upper surface of the left end side portion of the left yoke piece 37 of the upper setting yoke 36, and the lower end surface of the right magnet 65 is the right end side portion of the right yoke piece 38 of the upper setting yoke 36. Is in contact with the top surface of the magnet.

Further, the volumes of the left magnet 64 and the right magnet 65 forming the second magnetic circuit are larger than the volumes of the left magnet 62 and the right magnet 63 forming the first magnetic circuit, respectively. As a result, the respective magnetic forces of the left magnet 64 and the right magnet 65 forming the second magnetic circuit are larger than the respective magnetic forces of the left magnet 62 and the right magnet 63 forming the first magnetic circuit.

Even with the elevating counter 61 having such a configuration, the same operation and effect as the elevating counter 21 of the first embodiment described above can be obtained. Further, according to the elevating counter 61, the magnetic forces of the left magnet 64 and the right magnet 65 forming the second magnetic circuit are combined with the magnetic forces of the left magnet 62 and the right magnet 63 forming the first magnetic circuit. By making them different, it is possible to create a difference in strength between the first magnetic field formed by the first magnetic circuit and the second magnetic field formed by the second magnetic circuit. As described above, according to the elevating counter 61 of the present embodiment, the degree of freedom in setting the strength of the first magnetic field and the strength of the second magnetic field can be increased.

The left magnet 62 and the right magnet 63 are specific examples of the "pair of first magnets" in the claims, and the left magnet 64 and the right magnet 65 are the "pair of first magnets" in the claims. This is a specific example of "2 magnets".

[Third Embodiment]
FIG. 9 schematically shows the elevating counter 71 according to the third embodiment of the present invention. In FIG. 9, the same components as those of the elevating counter 21 of the first embodiment of the present invention are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 9, the elevating counter 71 is formed by adding a magnetic field variable yoke 72 to the elevating counter 21 of the first embodiment. The magnetic field variable yoke 72 is arranged below the lower setting yoke 33 so as to face the lower setting yoke 33. Further, in downward view, the left portion of the magnetic field variable yoke 72 overlaps the right portion of the yoke piece 34, and the right portion of the magnetic field variable yoke 72 overlaps the yoke piece 35 and the left portion. Further, the central portion in the left-right direction of the magnetic field variable yoke 72 is located below the central portion in the left-right direction of the magnetic sensor 22. Further, the magnetic field variable yoke 72 is fixed to the upper mold holder 7 together with the magnetic field variable yoke 41. The magnetic field variable yoke 72 and the magnetic field variable yoke 41 move upward at the same time when the upper mold holder 7 rises, and move downward at the same time when the upper mold holder 7 descends. The magnetic field variable yoke 72 of the third embodiment is a specific example of the "first magnetic field variable yoke" in the claims, and the magnetic field variable yoke 41 of the third embodiment is the "first magnetic field variable yoke" in the claims. This is a specific example of "2 magnetic field variable yoke".

When the upper mold holder 7 is in the upper limit position, as shown in FIG. 9A, the magnetic field variable yoke 41 is located at a position separated from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more. The magnetic field variable yoke 72 is located at a position less than a predetermined distance downward from the lower surface of each yoke piece 37, 38 of the lower setting yoke 33. On the other hand, when the upper mold holder 7 descends and moves to its lower limit position, as shown in FIG. 9B, the magnetic field variable yoke 41 moves upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36. The magnetic field variable yoke 72 moves to a position less than the predetermined distance, and the magnetic field variable yoke 72 moves downward from the lower surface of each yoke piece 37, 38 of the lower setting yoke 33 to a position separated by a predetermined distance or more. Both H1 in FIGS. 9 (A) and 9 (B) indicate positions separated from the upper surface of each of the yoke pieces 37 and 38 of the upper setting yoke 36 by a predetermined distance upward. Further, H2 in FIGS. 9 (A) and 9 (B) both indicate positions separated from the lower surface of each of the yoke pieces 37 and 38 of the lower setting yoke 33 by a predetermined distance downward. In FIG. 9A, the position of the magnetic field variable yoke 41 is higher than the position H1, and the position of the magnetic field variable yoke 72 is higher than the position H2. In FIG. 9B, the position of the magnetic field variable yoke 41 is lower than the position H1, and the position of the magnetic field variable yoke 72 is lower than the position H2.

Further, in FIG. 9, the N pole at the lower part of the left magnet 31, the S pole at the lower part of the right magnet 32, and the lower setting yoke 33 have the direction of the magnetic field in one direction (right direction) in the extension direction of the magnetic element 23. A first magnetic circuit is formed in which a first magnetic field is applied to the magnetic element 23. Further, the north pole of the upper part of the right side magnet 32, the S pole of the upper part of the left side magnet 31, and the upper setting yoke 36 have a second magnetic field whose magnetic field direction is the other direction (left direction) in the extension direction of the magnetic element 23. A second magnetic circuit is formed.

Further, in the present embodiment, (1) the distance between the yoke pieces 37, 38 of the upper setting yoke 36 and the axis of the magnetic element 23, and the yoke pieces 34, 35 of the lower setting yoke 33 and the magnetic element 23. Equal to the distance to the axis. (2) The yoke pieces 37 and 38 of the upper setting yoke 36 are formed to have the same shape as the yoke pieces 34 and 35 of the lower setting yoke 33, respectively. That is, no protrusion is formed on the right end side portion of the yoke piece 37 and the left end side portion of the yoke piece 38. (3) The distance between the right end of the yoke piece 37 and the left end of the yoke piece 38 in the upper setting yoke 36 is the distance between the right end of the yoke piece 34 and the left end of the yoke piece 35 in the lower setting yoke 33. Is equal to. If the magnetic field variable yoke 41 and the magnetic field variable yoke 72 are removed due to the configurations (1) to (3), the strength of the first magnetic field applied to the magnetic element 23 and the strength of the second magnetic field are equal to each other.

As shown in FIG. 9A, the magnetic field variable yoke 41 is located at a position upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more, and the magnetic field variable yoke 72 is on the lower side. When the setting yoke 33 is located at a position less than a predetermined distance downward from the lower surface of each yoke piece 34, 35, the magnetic field line in the first magnetic field passes through the magnetic field variable yoke 72, and the magnetic field line in the second magnetic field is the magnetic element 23. It will pass through. As a result, the magnetization direction of the magnetic element 23 becomes a direction corresponding to the direction of the second magnetic field, that is, the left direction. On the other hand, as shown in FIG. 9B, the magnetic field variable yoke 41 is located at a position less than a predetermined distance upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36, and the magnetic field variable yoke 72 is below. When the yoke pieces 34 and 35 of the side setting yoke 33 are separated downward by a predetermined distance or more, the magnetic field lines in the first magnetic field pass through the magnetic element 23, and the magnetic field lines in the second magnetic field are magnetic field variable yokes. It will pass through 41. As a result, the magnetization direction of the magnetic element 23 becomes the direction corresponding to the direction of the first magnetic field, that is, the right direction.

As can be seen from the above description, the magnetic field variable yoke 41 is located on the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 from a position separated upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 by a predetermined distance or more. The lower setting yoke 33 moves upward from the position less than the predetermined distance, and the magnetic field variable yoke 72 moves downward from the lower surface of each yoke piece 34, 35 of the lower setting yoke 33 to a position less than the predetermined distance. When the upper mold holder 7 is moved downward from the lower surface of each of the yoke pieces 34 and 35 to a position separated by the predetermined distance or more, that is, when the upper mold holder 7 is moved from the upper limit position to the lower limit position, the magnetization direction of the magnetic element 23 is to the left. Flip to the right from. On the other hand, the magnetic field variable yoke 41 is a predetermined distance upward from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36 from a position less than the above predetermined distance from the upper surface of each yoke piece 37, 38 of the upper setting yoke 36. Each yoke piece of the lower setting yoke 33 is moved to a position more distant than that, and the magnetic field variable yoke 72 is moved downward from the lower surface of each yoke piece 34, 35 of the lower setting yoke 33 from a position separated by the above-mentioned predetermined distance or more. When the upper mold holder 7 is moved downward from the lower surfaces of 34 and 35 to a position less than a predetermined distance, that is, when the upper mold holder 7 is moved from the lower limit position to the upper limit position, the magnetization direction of the magnetic element 23 is reversed from the right direction to the left direction. ..

Even with the elevating counter 71 having such a configuration, it is possible to detect the elevating of the upper mold holder 7 based on a small amount of movement of the magnetic field variable yokes 41 and 72, so that a small elevating counter can be realized. Further, by controlling the path of the magnetic field lines by using the lower setting yoke 33 and the upper setting yoke 36, the left magnet 31 and the right magnet 32 can be made smaller, respectively, and the elevating counter 21 can be made smaller. , It is possible to make it less susceptible to the influence of external magnetic noise, and it is possible to improve the detection accuracy and the stability of the elevation of the upper mold holder 7.

In each of the above embodiments, the distance between the magnetic field variable yoke 41 and the yoke pieces 37, 38 is changed by moving the magnetic field variable yoke 41 in a direction perpendicular to the upper surface of the yoke pieces 37, 38. The case is taken as an example, but the present invention is not limited to this. By moving the magnetic field variable yoke 41 in a direction parallel to the upper surface of the yoke pieces 37, 38, the distance between the magnetic field variable yoke 41 and the yoke pieces 37, 38 may be changed. For example, as shown in FIG. 10, in the elevating counter 21 of the first embodiment, the portion other than the magnetic field variable yoke 41 is bracketed so that the upper surfaces of the yoke pieces 34, 35, 37, and 38 are in the vertical direction. It is attached to the lower mold holder 6 via 81. Further, the magnetic field variable yoke 41 is attached to the upper mold holder 7 via the bracket 82 so that the lower surface thereof is in the vertical direction. Looking at the elevating counter 21 from the direction of arrow XI-XI in FIG. 10, it becomes as shown in FIG. As shown in FIG. 11A, when the upper mold holder 7 is in the upper limit position, the distance between the magnetic field variable yoke 41 and the yoke pieces 37, 38 of the upper setting yoke 36 is a predetermined distance or more. On the other hand, as shown in FIG. 11B, when the upper mold holder 7 is in the lower limit position, the magnetic field variable yoke 41 overlaps with the right portion of the yoke piece 37 and the left portion of the yoke piece 38, and the magnetic field variable yoke 41 The distance between the upper setting yoke 36 and the yoke pieces 37, 38 of the upper setting yoke 36 is less than a predetermined distance. In this way, when the upper mold holder 7 moves between the upper limit position and the lower limit position, the magnetic field variable yoke 41 moves in a direction parallel to the upper surfaces of the yoke pieces 37 and 38. The configuration in which the magnetic field variable yoke 41 is moved in a direction parallel to the upper surfaces of the yoke pieces 37 and 38 is also equivalent to the configuration in which the magnetic field variable yoke 41 is moved in a direction perpendicular to the upper surfaces of the yoke pieces 37 and 38. Action effect can be obtained.

Further, in the first embodiment, the case where the protrusions 39 and 40 are formed on the right end side portion of the yoke piece 37 of the upper setting yoke 36 and the left end side portion of the yoke piece 38 has been given as an example. By forming the protrusions 39 and 40 at the ends of the yoke pieces 37 and 38 facing each other, it is possible to increase the density of the magnetic field lines that enter the magnetic element 23 from the yoke piece 38 and exit from the magnetic element 23 to the yoke piece 37. The second magnetic field applied to the magnetic element 23 can be strengthened. Therefore, by forming the protrusions 39 and 40 on the yoke pieces 37 and 38 of the upper setting yoke 36 and not forming the protrusions on the yoke pieces 34 and 35 of the lower setting yoke 33, the second portion applied to the magnetic element 23 is applied. It is possible to create a difference in strength between the magnetic field and the first magnetic field applied to the magnetic element 23. However, the method of creating a difference in strength between the second magnetic field applied to the magnetic element 23 and the first magnetic field applied to the magnetic element 23 is not limited to this depending on the shapes of the yoke pieces 34, 35, 37, and 38. For example, by forming recesses at the ends of the pair of yoke pieces of the lower setting yoke facing each other, the density of the magnetic field lines entering and exiting the magnetic element 23 through these yoke pieces may be reduced. Further, the shapes of the yoke pieces 34, 35, 37, and 38 are made the same, the distance D3 between the right end 34A of the yoke piece 34 and the left end 35A of the yoke piece 35, and the right end 37A of the yoke piece 37 and the yoke piece 38. By making the distance D4 between the left end 38A different from each other, it is possible to create a difference in strength between the second magnetic field applied to the magnetic element 23 and the first magnetic field applied to the magnetic element 23.

Further, in the first embodiment, the case where the magnetic field variable yoke 41 is arranged so as to overlap the right portion of the yoke piece 37 of the upper setting yoke 36 and the left portion of the yoke piece 38 in the upward view has been given as an example. The present invention is not limited to this. The magnetic field variable yoke 41 may be arranged so as to overlap the other parts of the yoke piece 37 and the yoke piece 38. In upward view, the magnetic field variable yoke 41 is placed between the magnetic field variable yoke 41 and the yoke pieces 37, 38 by simultaneously overlapping any part of the yoke piece 37 with any part of the yoke piece 38. When the distance is less than the predetermined distance, the path of the magnetic field lines from the N pole of the right side magnet 32 to the S pole of the left side magnet 31 can be changed to reduce the density of the magnetic field lines passing through the magnetic element 23.

Further, in each of the above embodiments, the portion of the elevating counter 21 (61, 71) excluding the magnetic field variable yoke 41 is attached to the non-moving lower mold holder 6, and the magnetic field variable yoke 41 is attached to the moving upper mold holder 7. However, the portion of the elevating counter 21 (61, 71) excluding the magnetic field variable yoke 41 may be attached to the moving upper mold holder 7, and the magnetic field variable yoke 41 may be attached to the non-moving lower mold holder 6.

Further, in each of the above embodiments, as the magnetic element 23, a magnetic element having a larger coercive force in the central portion than in the outer peripheral side portion of the magnetic element is used, but the central portion is larger than the outer peripheral side portion of the magnetic element. A magnetic element having a smaller coercive force may be used.

Further, the present invention can be appropriately modified within the scope of the claims and within a range not contrary to the gist or idea of the invention that can be read from the entire specification, and the motion detection device and the mold device with such a change are also included in the present invention. It is included in the technical idea of the invention.

1 Mold device 2 Work material 3 Mold 4 Lower mold (second mold piece)
5 Upper mold (first mold piece)
6 Lower mold holder (second support part)
7 Upper mold holder (first support part)
8 Guide post (third support)
21, 61, 71 Lifting counter (motion detection device)
22 Magnetic sensor 23 Magnetic element 31 Left magnet (first common magnet)
32 Right side magnet (second common magnet)
33 Lower setting yoke (first setting yoke)
34, 35 yoke pieces (first yoke piece)
36 Upper setting yoke (second setting yoke)
37, 38 York piece (second yoke piece)
41, 72 Magnetic field variable yoke 45 Count circuit 62 Left magnet (first magnet)
63 Right magnet (first magnet)
64 Left magnet (second magnet)
65 Right magnet (second magnet)

Claims (13)

A motion detection device that detects the relative motion of a first object with respect to a second object.
A magnetic sensor provided on the second object and having a magnetic element that extends linearly and whose magnetization direction changes according to the direction of a magnetic field applied from the outside .
A pair of first magnets provided on the second object and forming a first magnetic field in which the direction of the magnetic field applied to the magnetic element is one direction in the extension direction of the magnetic element.
In a region provided on the second object and separated from the magnetic element in one direction orthogonal to the extension direction, the magnetic element is arranged on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, respectively. It has a pair of first yoke pieces, and the path of the magnetic field lines in the first magnetic field is set so that the magnetic field lines in the first magnetic field pass through the magnetic element in one direction in the extension direction of the magnetic element. First setting yoke and
The first magnetic field provided on the second object, the direction of the magnetic field applied to the magnetic element is the extension direction of the magnetic element, and the strength of the magnetic field applied to the magnetic element is applied to the magnetic element. A pair of second magnets that form a second magnetic field that is stronger than
In a region provided on the second object and separated from the magnetic element in another direction orthogonal to the extension direction, the magnetic element is arranged on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, respectively. It has a pair of second yoke pieces, and the path of the magnetic field lines in the second magnetic field is set so that the magnetic field lines in the second magnetic field pass through the magnetic element in the other direction in the extension direction of the magnetic element. Second setting yoke and
When it is provided on the first object, moves relative to the second setting yoke , and the distance to the second setting yoke is a predetermined distance or more, and the distance to the second setting yoke . Is provided with a magnetic field variable yoke that changes the strength of the second magnetic field applied to the magnetic element by changing the path of the magnetic field lines in the second magnetic field when the distance is less than the predetermined distance. Motion detection device. The magnetic field variable yoke moves relative to the pair of second yoke pieces, and when the distance from the pair of second yoke pieces is equal to or greater than the predetermined distance, the magnetic field variable yoke is set by the second setting yoke. The path of the magnetic field lines in the second magnetic field is maintained, and when the distance to the pair of second yoke pieces is less than the predetermined distance, the magnetic field lines in the second magnetic field pass through the magnetic field variable yoke. The motion detection device according to claim 1 , wherein the path of the magnetic field line in the second magnetic field set by the second setting yoke is changed. When the distance between the variable magnetic field yoke and the pair of second yoke pieces is equal to or greater than the predetermined distance, the variable magnetic field yoke follows the path of the magnetic field lines in the second magnetic field set by the second setting yoke. By maintaining the state, the strength of the second magnetic field applied to the magnetic element is stronger than the strength of the first magnetic field applied to the magnetic element, and the magnetic field variable yoke and the pair of second yokes are maintained. When the distance to the piece is less than the predetermined distance, the path of the magnetic field lines in the second magnetic field set by the second setting yoke so that the magnetic field lines in the second magnetic field pass through the inside of the magnetic field variable yoke. The motion according to claim 1 or 2, wherein by changing the above, the strength of the second magnetic field applied to the magnetic element is made weaker than the strength of the first magnetic field applied to the magnetic element. Detection device. Any of claims 1 to 3 , wherein the shape of each of the pair of second yoke pieces facing each other is different from the shape of each of the pair of first yoke pieces facing each other. The motion detection device described in Crab . The motion detection device according to claim 1 , wherein the distance between the pair of second yoke pieces is different from the distance between the pair of first yoke pieces. Any of claims 1 to 5 , wherein the distance between the magnetic element and the pair of second yoke pieces is different from the distance between the magnetic element and the pair of first yoke pieces . The motion detection device described in Crab. The motion detection device according to any one of claims 1 to 6 , wherein the magnetic force of each of the pair of second magnets is different from the magnetic force of each of the pair of first magnets. A motion detection device that detects the relative motion of a first object with respect to a second object.
A magnetic sensor provided on the second object and having a magnetic element that extends linearly and whose magnetization direction changes according to the direction of a magnetic field applied from the outside .
A pair of first magnets provided on the second object and forming a first magnetic field in which the direction of the magnetic field applied to the magnetic element is one direction in the extension direction of the magnetic element.
In a region provided on the second object and separated from the magnetic element in one direction orthogonal to the extension direction, the magnetic element is arranged on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, respectively. It has a pair of first yoke pieces, and the path of the magnetic field lines in the first magnetic field is set so that the magnetic field lines in the first magnetic field pass through the magnetic element in one direction in the extension direction of the magnetic element. First setting yoke and
A pair of second magnets provided on the second object and forming a second magnetic field in which the direction of the magnetic field applied to the magnetic element is the other direction of the extension direction of the magnetic element.
In a region provided on the second object and separated from the magnetic element in another direction orthogonal to the extension direction, the magnetic element is arranged on one side in the extension direction of the magnetic element and on the other side in the extension direction of the magnetic element, respectively. It has a pair of second yoke pieces, and the path of the magnetic field lines in the second magnetic field is set so that the magnetic field lines in the second magnetic field pass through the magnetic element in the other direction in the extension direction of the magnetic element. Second setting yoke and
It moves relative to the first setting yoke , and when the distance to the first setting yoke is equal to or greater than the first predetermined distance and the distance to the first setting yoke is the first predetermined distance. A first magnetic field variable yoke that changes the strength of the first magnetic field applied to the magnetic element by changing the path of the magnetic field lines in the first magnetic field when the distance is less than the distance.
It moves relative to the second setting yoke , and when the distance to the second setting yoke is equal to or greater than the second predetermined distance and the distance to the second setting yoke is the second predetermined distance. It is characterized by having a second magnetic field variable yoke that changes the strength of the second magnetic field applied to the magnetic element by changing the path of the magnetic field lines in the second magnetic field when the distance is less than the distance. Motion detection device. The first magnetic field variable yoke is the distance between the first magnetic field variable yoke and the first setting yoke when the first object moves relative to the second object in one direction. Increases, and the distance between the first magnetic field variable yoke and the first set yoke decreases when the first object moves relative to the second object in the other direction. Provided on the first object,
The second magnetic field variable yoke is the distance between the second magnetic field variable yoke and the second set yoke when the first object moves relative to the second object in one direction. Becomes smaller, and the distance between the second magnetic field variable yoke and the second set yoke becomes larger when the first object moves relative to the second object in the other direction. Provided on the first object,
The first magnetic field variable yoke is set by the first setting yoke when the distance between the first magnetic field variable yoke and the first setting yoke is equal to or greater than the first predetermined distance. When the distance between the first magnetic field variable yoke and the first set yoke is less than the first predetermined distance, the magnetic field lines in the first magnetic field are the first. The path of the magnetic field lines in the first magnetic field set by the first setting yoke is changed so as to pass through the magnetic field variable yoke.
The second magnetic field variable yoke is set by the second setting yoke when the distance between the second magnetic field variable yoke and the second setting yoke is equal to or greater than the second predetermined distance. When the distance between the second magnetic field variable yoke and the second set yoke is less than the second predetermined distance, the magnetic field lines in the second magnetic field are the second magnetic field lines. The path of the magnetic field lines in the second magnetic field set by the second setting yoke is changed so as to pass through the magnetic field variable yoke.
As the first object moves relative to the second object in one direction, the distance between the first magnetic field variable yoke and the first set yoke is equal to or greater than the first predetermined distance. When the distance between the second variable magnetic field yoke and the second set yoke is less than the second predetermined distance, the strength of the second magnetic field applied to the magnetic element is the magnetic element. The strength of the first magnetic field is weaker than that of the first magnetic field, and the first object moves relative to the second object in the other direction, whereby the first magnetic field variable yoke and the first magnetic field are variable. When the distance to the setting yoke is less than the first predetermined distance and the distance between the second magnetic field variable yoke and the second setting yoke is equal to or more than the second predetermined distance, the magnetic element The motion detection device according to claim 8, wherein the strength of the second magnetic field applied to the magnetic element is stronger than the strength of the first magnetic field applied to the magnetic element. One magnet of the pair of first magnets and one magnet of the pair of second magnets are formed by a single first common magnet, and among the pair of first magnets. The motion according to any one of claims 1 to 9 , wherein the other magnet of the pair and the other magnet of the pair of second magnets are formed by a single second common magnet. Detection device. The number of times the magnetization direction of the magnetic element changes from one direction of extension of the magnetic element to the other direction of extension, and the number of times the magnetization direction of the magnetic element changes from the other direction of extension of the magnetic element to one direction of extension. The motion detection device according to any one of claims 1 to 10 , further comprising a counting circuit for counting one or both. The motion detection device according to any one of claims 1 to 11 , wherein the magnetic element is a magnetic element that produces a large Barkhausen effect. It has a first mold piece and a second mold piece, a work material is sandwiched between the first mold piece and the second mold piece, and the work material is pressed against the work material. The mold to be processed and
A first support portion that supports the first mold piece, and
A second support portion that supports the second mold piece, and
A third that movably supports the first support portion with respect to the second support portion so that the first mold piece comes into contact with and separates from the second mold piece. Support part and
The motion detection device according to any one of claims 1 to 12 is provided.
The first object is the first support portion.
The second object is the second support portion.
The motion detection device is a mold device for detecting the relative movement of the first support portion with respect to the second support portion .

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